Implantable medical electrical stimulation lead fixation method and apparatus

Abstract

An implantable medical electrical lead particularly for stimulation of the sacral nerves comprises a lead body extending between a distal end and a proximal end, and the distal end having at least one electrode of an electrode array extending longitudinally from the distal end toward the proximal end. The lead body at its proximal end may be coupled to a pulse generator, additional intermediate wiring, or other stimulation device. A fixation mechanism is formed on or integrally with the lead body proximal to the electrode array that is adapted to be implanted in and engage subcutaneous tissue, particularly muscle tissue, to inhibit axial movement of the lead body and dislodgement of the stimulation electrodes. The fixation mechanism comprises a M tine elements arrayed in a tine element array along a segment of the lead proximal to the stimulation electrode array. Each tine element comprises at least N flexible, pliant, tines, each tine having a tine width and thickness and extending through a tine length from an attached tine end to a free tine end. The attached tine end is attached to the lead body from a tine attachment site and supports the tine extending outwardly of the lead body and proximally toward the lead proximal end. The M×N tines are adapted to be folded inward against the lead body when fitted into and constrained by the lumen of an introducer such that the tine free ends of more distal tines of more distal tine elements are urged toward or alongside the attached tine ends of the adjacent more proximal tines of more proximal tine elements, and the folded tines do not overlap one another.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention relates generally to a method and apparatus that allows for stimulation of body tissue, particularly sacral nerves. More specifically, this invention relates to an implantable medical electrical lead having at least one stimulation electrode adapted to be implanted near the sacral nerves for stimulation of a bundle of sacral nerve fibers and a fixation mechanism for providing chronic stability of the stimulation electrode and lead. Moreover, this invention relates to the method of implantation and anchoring of the medical electrical lead electrodes in operative relation to a selected sacral nerve to allow for stimulation. [0003] 2. Description of Related Art [0004] Pelvic floor disorders such as, urinary incontinence, urinary urge / frequency, urinary retention, pelvic pain, bowel dysfunction (constipation, diarrhea), erectile dysfunction, are bodily functions influenced by the sacral nerves. Specifical...

AI Technical Summary

Benefits of technology

[0024] The present invention recognizes and provides a solution to the problems associated with implanting and maintaining electrical leads in body tissue, particularly muscle tissue to maintain one or more lead electrode in relation to a particular body site, through use of minimally invasive implantation techniques. In a preferred embodiment, the present invention maintains one or more sacral nerve stimulation electrode in close proximity or casual contact with discrete nerve fibers of the

Problems solved by technology

Many of the pharmaceuticals do not adequately resolve the issue and can cause unwanted side effects, and a number of the surgical procedures have a low success rate and are not reversible.

These solutions have drawbacks well known to those skilled in the art.

In addition, some disease states do not have adequate medical treatments.

A problem associated with implantation of permanent and temporary neurostimulation leads involves maintaining the discrete ring-shaped electrode(s) in casual contact, that is in location where slight contact of the electrode with the sacral nerve may occur or in close proximity to the sacral nerve to provide adequate stimulation of the sacral nerve, while allowing for some axial movement of the lead body.

Typically, physicians spend a great deal of time with the patient under a general anesthetic placing the leads due to the necessity of making an incision exposing the foramen and due to the difficulty in optimally positioning the small size stimulation electrodes relative to the sacral nerve.

The patient is thereby exposed to the additional dangers associated with extended periods of time under a general anesthetic.

As can be appreciated, unintended movement of any object positioned proximate a nerve may cause unintended nerve damage.

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